The present invention relates to fasteners for automotive components, and relates particularly, but not exclusively, to fasteners for securing an undercover panel to the underside of a vehicle floor.
Undercover panels are generally secured to the underside of a vehicle floor in order to cover components such as exhaust pipes, fuel lines and brake lines, in order to improve the aerodynamic efficiency of the vehicle. Undercover panels are generally made of thermoplastic materials, although it is becoming increasingly popular to use fabric materials to form such panels, which provide a more lightweight undercover panel than one made from thermoplastic material, and provide various manufacturing advantages. An example of a textile undercover panel of this type is supplied by Johann Borgers GmbH & Co. KG, Borgersstrasse, 46397 Bocholt, Germany. However, the use of fabric undercover panels also causes difficulties in securing the undercover panel to the underside of the vehicle, mainly because of the increased flexibility of the undercover panel compared with one made of thermoplastic material.
Fasteners for attaching sheet-like materials such as undercover panels to the underside of a vehicle are well known. For example, EP 1350712 discloses a fastener for attaching an undercover panel to a weld stud on the underside of a floor panel of a car body. The fastener comprises a pair of clips which are assembled to each other at an aperture in the undercover panel, from opposite sides of the undercover panel. The undercover panel with fasteners assembled thereto is then mounted to the underside of the car body by being pushed onto a weld stud on the vehicle underside during final vehicle assembly.
U.S. Pat. No. 5,871,320 discloses a retaining device for securing a layer of insulation material to sheet metal in the construction of motor vehicle interiors. The retaining device is formed as a single piece, and has a flange for abutting the surface of the layer of insulation material, and an articulated structure which can be inserted through a hole in the layer of insulation material. The articulated structure has locking fingers connected via live hinges to a push plate, so that flexing of the live hinges causes the layer of insulating material to be clamped between the locking fingers and the flange. The layer of insulating material with fasteners secured thereto is then pushed onto a weld stud on the sheet metal.
DE 102006007244 discloses a fastener formed as a single element by means of injection moulding and having first and second parts connected to each other by a frangible portion adapted to bleak when a predetermined axial compressive load is applied to the fastener. The fastener has a threaded portion for mounting to a weld stud, a flange for engaging a component and an anchor portion having flexible fingers which provide the fastener with a larger diameter than an aperture in the component to which the fastener is to be mounted. The fastener is inserted through the aperture from one side thereof so that the flexible fingers flex and pass through the aperture, and as the flange comes into abutment with the component, the flexible fingers flex back to their original position to retain the fastener on the component. The two parts of the fastener are then pushed together, which fractures the frangible part to secure the two parts of the fastener to each other and clamp the component between the parts. The component with fasteners secured thereto is then screwed onto a weld stud.
EP 1849687 discloses a fastener for attaching an undercover to the underside of a vehicle floor panel. The fastener comprises first and second tubular clips which are pushed together from opposite sides of the undercover material to clamp the undercover between the two clips of the fastener. The undercover with fasteners secured thereto is then mounted to a weld stud which is inserted into a bore of the fastener.